Electrocatalyst for alcohol oxidation in fuel cells

Abstract

Binary and ternary electrocatalysts are provided for oxidizing alcohol in a fuel cell. The binary electrocatalyst includes 1) a substrate selected from the group consisting of NiWO4 or CoWO4 or a combination thereof, and 2) Group VIII noble metal catalyst supported on the substrate. The ternary electrocatalyst includes 1) a substrate as described above, and 2) a catalyst comprising Group VIII noble metal, and ruthenium oxide or molybdenum oxide or a combination thereof, said catalyst being supported on said substrate.

Description

The present invention relates to electrocatalyst compositions. More specifically, the invention relates to electrocatalysts which can be used on the anode of a fuel cell to oxidize alcohol.A fuel cell is an electrochemical device with an anode and a cathode that converts chemical energy provided by a fuel and an oxidant into electricity. An electrolyte is required which is in contact with both electrodes and which may be alkaline, acidic, solid or liquid. The basic process is highly efficient and essentially pollution-free. Also, since single fuel cells can be assembled in stacks of varying sizes, systems can be designed to produce a wide range of output levels.As an energy conversion device, the fuel cell is distinguished from a conventional battery by its fuel storage capacity. Unlike a battery which consumes internally stored fuel and needs to be either discarded or recharged after a certain time, fuel is fed to the fuel cell from an external source giving the fuel cell a practic...

AI Technical Summary

Benefits of technology

By using the anodes of the invention to oxidize alcohol in a fuel cell, carbon monoxide poisoning is significantly reduced. Other advantages include lower costs due to lower weight of noble metals, higher stability with respect to agglomeration, and their increased activity at higher overpotentials.

Problems solved by technology

Serious drawbacks have also been encountered in the storage of hydrogen for use in fuel cells.

A major obstacle in the development of methanol fuel cells is the loss of electrochemical activity of even the best electrocatalyst due to "poisoning" by carbon monoxide (CO).

It is well known that CO, even at levels of 1-10 ppm, is a severe poison to platinum electrocatalysts and significantly reduces fuel cell performance.

In spite of the foregoing, prior attempts to solve the problem of CO poisoning at the anode of methanol fuel cells have been unsuccessful.

Prior attempts to avoid the problem have proven to be too expensive, ineffective, or impractical to be commercially viable.

Images